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Chinese Journal of Chemistry 2011年第9期29卷 1951-1954页

作者： Zhang, jinfeng wu, Jincai Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province State Key Labora- tory of Applied Organic Chemistry College of Chemistry and Chemical Engineering Lanzhou University Lanzhou Gansu 730000 Chinan

A series of novel polylactide （PLA） polymers were synthesized initiated by 4-dicyanomethylene- 2-methyl-6-{4-[（2-hydroxyethyl）（methyl）amino]styryl}-4H-pyran （DCM） with Sn（Oct）2 as catalyst. The color and emi... 详细信息

关键词： color tuning emission polylactide polymer

Theoretical and experimental investigation on bridge-borne noise under moving high-speed train

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Science China(Technological Sciences) 2013年第4期56卷 917-924页

作者： ZHANG Xun LI XiaoZhen LIU QuanMin wu jinfeng LI YaDong MOE Key Laboratory of High-Speed Railway Engineering Southwest Jiaotong University School of Civil Engineering Southwest Jiaotong University

Bridge-borne noise pollution caused by train-induced bridge vibration has attracted more and more attentions due to its low-frequency *** order to investigate the numerical simulation technique of bridge-borne noise and noise reduction methods,a simply supported prestressed concrete (PC) box-girder bridge is adopted for *** on train-track-bridge interaction theory,the dynamic response of the bridge under a moving high-speed train is calculated in time-domain and assumed as the sound source of bridge-borne *** bridge-borne noise is estimated according to boundary element method (BEM) in *** time-frequency transform is conducted by fast Fourier transformation (FFT).The validity of the numerical simulation technique is verified through comparison with field measurement ***,noise reduction methods are proposed and corresponding effects are *** show that the proposed numerical simulation method is feasible and accurate in assessing bridge-borne *** dominant frequencies of bridge vibration and bridgeborne noise range from 40 Hz to125 Hz and from 31.5 Hz to 100 Hz,*** peak frequency of bridge-borne noise near the bottom plate is 63 *** the thickness of deck plate,adjusting the inclination of webs to 0°-12°,strengthening the boundary constraints and adding a longitudinal clapboard are very effective noise control measures.

关键词： bridge-borne noise train-induced vibration sound radiation elevated bridge numerical simulation noise reduction

Aerodynamic characteristics of a high-speed train crossing the wake of a bridge tower from moving model experiments

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Railway Engineering Science 2022年第2期30卷 221-241页

作者： jinfeng wu Xiaozhen Li C.S.Cai Dejun Liu Department of Bridge Engineering School of Civil EngineeringSouthwest Jiaotong UniversityChengduChina 610031 Department of Bridge Engineering School of TransportationSoutheast UniversityNanjingJiangsuChina Department of Civil and Environmental Engineering Louisiana State UniversityBaton RougeLA 70803USA College of Civil Engineering and Architecture Jiaxing UniversityJiaxing 314001ZhejiangChina

In a strong crosswind,the wake of a bridge tower will lead to an abrupt change of the aerodynamic forces acting on a vehicle passing through it,which may result in problems related to the transportation *** study investigates the transient aerodynamic characteristics of a high-speed train moving in a truss girder bridge and passing by a bridge tower in a wind *** scaled ratio of the train,bridge,and tower are 1:*** of various parameters such as the incoming wind speed,train speed,and yaw angle on the aerodynamic performance of the train were *** the sudden change mechanism of aerodynamic loads on the train when it crosses over the tower was further *** results show that the bridge tower has an apparent shielding effect on the train passing through it,with the influencing width being larger than the width of the *** train speed is the main factor affecting the influencing width of aerodynamic coefficients,and the mutation amplitude is mainly related to the yaw angle obtained by changing the incoming wind speed or train *** vehicle movement introduces an asymmetry of loading on the train in the process of approaching and leaving the wake of the bridge tower,which should not be neglected.

关键词： Vehicle aerodynamics Wind tunnel test Moving train Bridge tower Shielding effect Sudden change mechanism Truss bridge

Chassis tra fficability simulation and experiment of a LY1352JP forest tracked vehicle

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Journal of Forestry Research 2021年第3期32卷 1315-1325页

作者： Shufa Sun jinfeng wu Chunlong Ren Hualin Tang Jianwei Chen Wenliang Ma Jiangwei Chu College of Engineering and Technology Northeast Forestry UniversityHarbin 150040People’s Republic of China Harbin Song Jiang Tractor Co. Ltd.Harbin 150010People’s Republic of China College of Transportation Northeast Forestry UniversityHarbin 150040People’s Republic of China

Based on the analysis of complex terrains and current forest transportation equipment,a forest tracked vehicle prototype LY1352 JP was *** road model and the virtual prototype of the chassis were constructed using dynamic simulation software *** optimal tension of the vehicle as well as its capabilities for crossing trenches,climbing vertical walls,uphill and downhill slopes were *** simulation results showed that the optimum tension force of the chassis of the vehicle was 63 kN(kilonewton),accounting for 45%of the total vehicle *** maximum trench crossing width and vertical obstacle climbing height were 1.35 m and 0.45 m,*** maximum uphill and downhill angles were 50°and 45°,*** on the prototype capacity for crossing trenches,and uphill and downhill driving were carried *** test results were in agreement with the simulation results.A cross-country performance of a fire truck based on the tracked vehicle chassis was conducted in an old-growth *** verified that the vehicle has a strong forest trafficability performance and can meet the needs for forest transportation.

关键词： Tracked vehicle Chassis Tra fficability RecurDyn dynamics simulation

On the “Online and Offline Blended Teaching” Mode for Ideological and Political Theory Courses in Universities—A Case of “Introduction to Basic Principles of Marxism”

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Open Journal of Applied Sciences 2023年第9期13卷 1479-1488页

作者： jinfeng wu School of Marxism Zhejiang Yuexiu University of Foreign Languages Shaoxing China

With the deepening development of educational informatization, online and offline blended teaching, as a new teaching mode, is increasingly receiving widespread attention from educators [1]. At present, the reform of the “online and offline blended teaching” of ideological and political education courses directly affects the quality of talent cultivation in universities. The article takes the course “Introduction to Basic Principles of Marxism” as an example to explore the reform mode of “online and offline blended teaching” in ideological and political theory courses in universities from the aspects of reasonable allocation of class hours, design of online teaching activities, how to deepen classroom teaching offline, and diversified assessment modes. Furthermore, the article summarizes the experience of mode reform and promotes the deep development of the people-oriented education concept in ideological and political courses in universities, so as to achieve the ultimate goal of moral education in ideological and political education in universities.

关键词： Ideological and Political Theory Courses in Universities Online and Offline Blended Teaching Introduction to Basic Principles of Marxism

Aesthetic value of aeolian geomorphosites in the Kumtagh Desert,China

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Research in Cold and Arid Regions 2014年第1期6卷 59-65页

作者： jinfeng wu Xin Wang Feng Guo Lei Li College of Tourism and Environment Shaanxi Normal University

Tourism development of aeolian geomorphosites in the Kumtagh Desert is beneficial to both harmonious development of human-nature relationship and the sustainable development of the tourist industry in the Kumtagh Desert and its sur- rounding area. This paper adopts some research methods including field observation, expert assessment, and systematic investigation to analyze and evaluate the aesthetic value of aeolian geomorphosites in the Kumtagh Desert from three aspects of＂Beauty of Morphology＂, ＂Beauty of Color＂ and ＂Beauty of Forms＂. This research is a creative work in the field of aeolian geomorphosites combining the method of aeolian geomorphology and tourism geography.

关键词： Kumtagh Desert aeolian geomorphosites aesthetic value

Preoperative Acute Sleep Deprivation Causes Postoperative Pain Hypersensitivity and Abnormal Cerebral Function

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Neuroscience Bulletin 2022年第12期38卷 1491-1507页

作者： Meimei Guo Yuxiang wu Danhao Zheng Lei Chen Bingrui Xiong jinfeng wu Ke Li Li Wang Kangguang Lin Zongze Zhang Anne Manyande Fuqiang Xu Jie Wang Mian Peng Department of Anesthesiology Zhongnan Hospital of Wuhan UniversityWuhan 430071China Department of Health and Kinesiology School of Physical EducationJianghan UniversityWuhan 430056China State Key Laboratory of Magnetic Resonance and Atomic and Molecular Physics National Center for Magnetic Resonance in WuhanWuhan Institute of Physics and MathematicsInnovation Academy for Precision Measurement Science and TechnologyChinese Academy of Sciences-Wuhan National Laboratory for OptoelectronicsWuhan 430071China Department of Anesthesiology Peking University Third HospitalBeijing 100191China Department of Afective Disorders The Afliated Brain Hospital of Guangzhou Medical UniversityGuangzhou 510000China School of Human and Social Sciences University of West LondonLondon W1S 3PRUK Institute of Neuroscience and Brain Disease Xiangyang Central HospitalAfliated Hospital of Hubei University of Arts and ScienceXiangyang 441000China University of Chinese Academy of Sciences Beijing 100049China

Preoperative sleep loss can amplify post-operative mechanical ***,the underlying mechanisms are still largely *** the current study,rats were randomly allocated to a control group and an acute sleep deprivation(ASD)group which experienced 6 h ASD before *** the variations in cerebral function and activity were investigated with multi-modal techniques,such as nuclear magnetic resonance,functional magnetic resonance imaging,c-Fos immunofluorescence,and *** results indicated that ASD induced hyperalgesia,and the metabolic kinetics were remarkably decreased in the striatum and *** functional connectivity(FC)between the nucleus accumbens(NAc,a subregion of the ventral striatum)and the ventrolateral periaqueductal gray(vLPAG)was significantly reduced,and the c-Fos expression in the NAc and the vLPAG was ***,the electrophysiological recordings demonstrated that both the neuronal activity in the NAc and the vLPAG,and the coherence of the NAc-vLPAG were suppressed in both resting and task *** study showed that neuronal activity in the NAc and the vLPAG were weakened and the FC between the NAc and the vLPAG was also suppressed in rats with ASD-induced *** study highlights the importance of preoperative sleep management for surgical patients.

关键词： Acute sleep deprivation Incisional pain Nucleus accumbens Periaqueductal gray Functional connectivity

Comparison between SSR and SNP systems of genetic diversity analysis in Brassica napus L.

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Oil Crop Science 2018年第2期3卷 86-91页

作者： Kun Xu jinfeng wu Feng Li Xiaoming wu Key Laboratory of Biology and Genetic Improvement of Oil Crops Ministry of AgricultureOil Crops Research InstituteChinese Academy of Agricultural Sciences

Simple sequence repeat(SSR) capillary electrophoresis and single nucleotide polymorphism(SNP) array are widely used tools for investigating genetic diversity. However, efficiency between SSR and SNP on rapeseed genetic diversity has not been systematically assessed yet. In this study, both SSR and SNP were used on 446 worldwide B. napus germplasm lines. Data shows that 65 pairs of primers(70 SSRs) and 250 SNPs were necessary to identify the similar accessions. Furthermore, no significant differences were found between 2 systems on basic statistics, population structures, principal components and kinship parameters. In general, either SSR or SNP is efficient for genetic diversity estimation. However, our data revealed the fact that SNP array system shows slightly more accuracy than SSR system on ecotype groups division.

关键词： SSR capillary electrophoresis SNP array genetic diversity population structure,principal component

入境外国旅游流网络分布、性质和结构特征研究

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干旱区资源与环境 2014年第7期28卷 177-182页

作者：吴晋峰陕西师范大学旅游与环境学院西安710062

拓展入境旅游外国市场是我国入境旅游业发展面临的重要任务之一。应用地图法研究了入境外国旅游流网络空间分布特征,应用社会网络分析法和复杂网络理论研究了该网络的性质和结构特征,结果表明:1)入境外国旅游流在中国的空间分布范围大... 详细信息

拓展入境旅游外国市场是我国入境旅游业发展面临的重要任务之一。应用地图法研究了入境外国旅游流网络空间分布特征,应用社会网络分析法和复杂网络理论研究了该网络的性质和结构特征,结果表明:1)入境外国旅游流在中国的空间分布范围大且不均衡,形成了两个"金三角",四个"银三角"和两个集中分布区。2)入境外国旅游流网络是无标度网络,网络中核心节点少,边缘节点多,核心节点的稳定和发展对全国入境旅游业的稳定和发展起重要的支撑和保障作用。3)网络中的节点可分为口岸、枢纽、中转、复合型等四种类型,分别发挥着旅游流出入境口岸、集聚和扩散、中转、多种功能复合等作用。4)入境外国旅游流在少数核心城市间转移和扩散,能大规模吸引和组织入境外国旅游流的目的地数量较少。

关键词：入境外国旅游流旅游流网络社会网络分析法复杂网络理论

Acid Value Determination and Pre-Esterification of Crude Euphorbia lathyris L. Oil

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World Journal of Engineering and Technology 2015年第2期3卷 70-75页

作者： Qiuyun Zhang jinfeng wu Peihua Ma Jie Cai Yutao Zhang School of Chemistry and Chemical Engineering Anshun University Anshun China Special and Key Laboratory of Functional Materials and Resource Chemistry of Guizhou Provincial Education Department Anshun University Anshun China School of Chemistry and Chemical Engineering Guizhou University Guiyang China School of Science Guizhou University Guiyang China

There were various problems in the determination of oil acid value of the national standard method, and this paper developed a low cost, simple and effective way to determine the acid value of oil and grease. Furthermore, the esterification of high acid Euphorbia lathyris L. oil (ELO) with methanol could be efficiently catalyzed by hydrochloric acid to produce biodiesel, and the influencing factors such as the amount of catalyst, reaction time, reaction temperature and molar ratio of oil to methanol were also studied. Under the optimized conditions with the oil to methanol molar ratio of 1:30 and a reaction temperature of 70℃, 95.8% oil conversion was obtained within 40 min in the presence of only 2.0 wt% of catalyst. Therefore, the low-cost non-edible Euphorbia lathyris L. oil as a raw material had good potential for the synthesis of biodiesel in industry.

关键词： Acid Value Pre-Esterification Euphorbia lathyris L. Oil Biodiesel